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package java.io;

import java.nio.charset.Charset;


Reads text from character files using a default buffer size. Decoding from bytes to characters uses either a specified charset or the platform's default charset. 
 The FileReader is meant for reading streams of characters. For reading streams of raw bytes, consider using a FileInputStream. 
Author:     Mark Reinhold
See Also:
Since:      1.1
/**
 * Reads text from character files using a default buffer size. Decoding from bytes
 * to characters uses either a specified {@linkplain java.nio.charset.Charset charset}
 * or the platform's
 * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
 *
 * <p>
 * The {@code FileReader} is meant for reading streams of characters. For reading
 * streams of raw bytes, consider using a {@code FileInputStream}.
 *
 * @see InputStreamReader
 * @see FileInputStream
 *
 * @author      Mark Reinhold
 * @since       1.1
 */
public class FileReader extends InputStreamReader {

   
Creates a new FileReader, given the name of the file to read, using the platform's default charset. 
Params:
  • fileName – the name of the file to read
Throws:
  • FileNotFoundException –  if the named file does not exist,
                  is a directory rather than a regular file,
                  or for some other reason cannot be opened for
                  reading.
/**
    * Creates a new {@code FileReader}, given the name of the file to read,
    * using the platform's
    * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
    *
    * @param fileName the name of the file to read
    * @exception  FileNotFoundException  if the named file does not exist,
    *                   is a directory rather than a regular file,
    *                   or for some other reason cannot be opened for
    *                   reading.
    */
    public FileReader(String fileName) throws FileNotFoundException {
        super(new FileInputStream(fileName));
    }

   
Creates a new FileReader, given the File to read, using the platform's default charset. 
Params:
  • file – the File to read
Throws:
  • FileNotFoundException –  if the file does not exist,
                  is a directory rather than a regular file,
                  or for some other reason cannot be opened for
                  reading.
/**
    * Creates a new {@code FileReader}, given the {@code File} to read,
    * using the platform's
    * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
    *
    * @param file the {@code File} to read
    * @exception  FileNotFoundException  if the file does not exist,
    *                   is a directory rather than a regular file,
    *                   or for some other reason cannot be opened for
    *                   reading.
    */
    public FileReader(File file) throws FileNotFoundException {
        super(new FileInputStream(file));
    }

   
Creates a new FileReader, given the FileDescriptor to read, using the platform's default charset. 
Params:
  • fd – the FileDescriptor to read
/**
    * Creates a new {@code FileReader}, given the {@code FileDescriptor} to read,
    * using the platform's
    * {@linkplain java.nio.charset.Charset#defaultCharset() default charset}.
    *
    * @param fd the {@code FileDescriptor} to read
    */
    public FileReader(FileDescriptor fd) {
        super(new FileInputStream(fd));
    }

   
Creates a new FileReader, given the name of the file to read and the charset. 
Params:
  • fileName – the name of the file to read
  • charset – the charset
Throws:
  • IOException –  if the named file does not exist,
                  is a directory rather than a regular file,
                  or for some other reason cannot be opened for
                  reading.
Since:11
/**
    * Creates a new {@code FileReader}, given the name of the file to read
    * and the {@linkplain java.nio.charset.Charset charset}.
    *
    * @param fileName the name of the file to read
    * @param charset the {@linkplain java.nio.charset.Charset charset}
    * @exception  IOException  if the named file does not exist,
    *                   is a directory rather than a regular file,
    *                   or for some other reason cannot be opened for
    *                   reading.
    *
    * @since 11
    */
    public FileReader(String fileName, Charset charset) throws IOException {
        super(new FileInputStream(fileName), charset);
    }

   
Creates a new FileReader, given the File to read and the charset. 
Params:
  • file – the File to read
  • charset – the charset
Throws:
  • IOException –  if the file does not exist,
                  is a directory rather than a regular file,
                  or for some other reason cannot be opened for
                  reading.
Since:11
/**
    * Creates a new {@code FileReader}, given the {@code File} to read and
    * the {@linkplain java.nio.charset.Charset charset}.
    *
    * @param file the {@code File} to read
    * @param charset the {@linkplain java.nio.charset.Charset charset}
    * @exception  IOException  if the file does not exist,
    *                   is a directory rather than a regular file,
    *                   or for some other reason cannot be opened for
    *                   reading.
    *
    * @since 11
    */
    public FileReader(File file, Charset charset) throws IOException {
        super(new FileInputStream(file), charset);
    }
}